In data centers, heat is generated by continuous and simultaneous operation of a large number of computing unit racks. Air cooling the whole room containing the data center is the most common method used to maintain thermal operating conditions in the data center. However, as data centers become increasingly larger in size, cooling them becomes more of a challenge. Thus, efficient heat dissipation and removal techniques have been pursued to reduce electrical power usage and to optimize operating performance.
Advances such as mobile measurement technology (MMT) have been proposed to measure temperature distributions and air flow in data centers to locally detect and cool areas with temperatures well above a desired level. See, for example, U.S. Pat. No. 7,366,632, issued to Hamann et al., entitled “Method and Apparatus for Three-Dimensional Measurements” (hereinafter “Hamann”), the contents of which are incorporated by reference herein. With MMT, a temperature sensor grid mounted on a cart is used to map out three dimensional temperature distributions in the data center. The sensors are mounted at various heights from the ground and lateral locations with spacing less than a foot apart.
A similar concept of sensor distribution on a grid is employed for air flow measurements inside the data centers. However, air movement is generally characterized by both airflow velocity and direction, making it a complex measurement since air direction can continuously change due to factors such as multiple cold air inlets combined with airflow from local fans mounted on computing units. For example, air is blown in various directions as the fans are usually positioned facing the hot spots in the room, and the air inlets redirect the airflow.
Therefore, improved techniques to measure airflow in a data center which are preferably compatible with MMT technology would be desirable.